過冷却水の凝固に及ぼす電場の影響に関する実験的検討 Experimental study on the effect of the electric filed on the freezing of the supercooled water
Effect of the electric field on freezing of supercooled water was investigated, experimentally. The experiment was carried out by charging the electrode whose tip was inserted into supercooled water. It was found that supercooled water freeze instantly by applying the electric charge. There were many papers in the past which dealt with the effect of electrical field on freezing of supercooled water, but with a high voltage, order of a few kV. However, through this experimental study, it was found that the supercooled water can freeze at the voltage less than 100V, if D.C. voltage is applied directly to supercooled water. There was no deformation of water droplet or spark discharge as some papers suggest as a reason for the effect. It was also found that the probability of freezing depends upon the degree of supercooling, value of D.C. voltage applied, size of electrode and the distance between two electrods. The mechanism of this effect was discussed and suggested as follows: High electric field is formed locally due to the existence of surface edge or small projections on the surface. Water molecule which has a polarity is drawn near to the cluster on the surface whose motion is restricted by the existence of electric field. Therefore, embryo can transform to nucleus, instantly.
日本冷凍空調学会論文集 14(1), 47-55, 1997-03-31